Disorder enabled band structure engineering of a topological insulator surface Journal Article

Author(s): Xu, Yishuai; Chiu, Janet; Miao, Lin; He, Haowei; Alpichshev, Zhanybek; Kapitulnik, Aharon; Biswas, Rudro R; Wray, Lewis A
Article Title: Disorder enabled band structure engineering of a topological insulator surface
Abstract: Three-dimensional topological insulators are bulk insulators with Z 2 topological electronic order that gives rise to conducting light-like surface states. These surface electrons are exceptionally resistant to localization by non-magnetic disorder, and have been adopted as the basis for a wide range of proposals to achieve new quasiparticle species and device functionality. Recent studies have yielded a surprise by showing that in spite of resisting localization, topological insulator surface electrons can be reshaped by defects into distinctive resonance states. Here we use numerical simulations and scanning tunnelling microscopy data to show that these resonance states have significance well beyond the localized regime usually associated with impurity bands. At native densities in the model Bi2X3 (X=Bi, Te) compounds, defect resonance states are predicted to generate a new quantum basis for an emergent electron gas that supports diffusive electrical transport.
Keywords: bismuth, electron, insulation, magnetic field, mathematical analysis, resonance, scanning tunnelling microscopy, tellurium, topology
Journal Title: Nature Communications
Volume: 8
ISSN: 2041-1723
Publisher: Nature Publishing Group  
Date Published: 2017-02-03
Start Page: Article number: 14081
Copyright Statement: CC BY
DOI: 10.1038/ncomms14081
Open access: yes (OA journal)